August 17, 2014 1:40pm EDTAugust 17, 2014 1:37pm EDTNadal delays his decision on defending his Open title as he recovers from a wrist injury. Former champ Juan del Potro makes his expected decision not to play.Rafael Nadal(AP Photo)

Del Porto is on the mend from a more serious wrist injury, one that required surgery in March. He won the 2009 men's title.

While playing in the Australian Open, Del Potro fought wrist pain that led to his operation. His long layoff saw him fall from the top-10 rankings for the first time in four years.

Nadal's injury is to his right wrist. He is a lefty but uses his right on a two-handed backhand shot. Images early last from his rehab sessions showed Nadal wearing a brace but hitting only with his left hand. Tests last week provided no unexpected results.

Inability to use his right wrist could have a major effect on Nadal's backhand. Reports indicate he hit last week with little power.

More recently, he was seen in practice sessions with Carlos Moya without the brace.